The expansion of complicated functions of many variables in Taylor polynomials is an important problem for many applications, and in practice can be performed rather conveniently (even to high… (More)

054401-1 Here we will derive the general theory of the beam-breakup instability in recirculating linear accelerators, in which the bunches do not have to be at the same rf phase during each… (More)

The Fortran-based environment COSY INFINTIY, as well as the related codes DAFOR and DAPRE, is presented. The codes contain modules for the computation of derivatives to very high orders in many… (More)

Multi-pass, multi-bunch beam-breakup has been long known to be a potential limiting factor for the current in linac-based recirculating accelerators. New understanding of theoretical and… (More)

PAC’03, Portland/OR Cornell University has proposed an Energy Recovery Linac (ERL) based synchrotron-light facility [1] which can provide improved X-ray radiation due to the high beam quality which… (More)

In very high energy storage rings the equilibrium spin polarization direction can vary strongly from point to point in phase space. Thus, unless counter measures are taken, the average polarization… (More)

Here we will derive the general theory of the beam-breakup (BBU) instability in recirculating linear accelerators with coupled beam optics and with polarized higher-order dipole modes. The bunches do… (More)

After the design luminosity of the electron-proton collider HERA had been exceeded [1,2], the interaction regions were rebuilt to obtain smaller b* at the two interaction points (IPs) [3,4,5]. Spin… (More)

In order to maximize the achievable luminosity of HERA the final focusing triplets of the lepton beam are installed close to the interaction point (IP). The dipole component of the magnets produces… (More)

Coherent beam-beam tune shift of unsymmetrical beam-beam interactions was studied experimentally and numerically in HERA, where the lepton beam has such a large beam-beam parameter (up to xi(y) =… (More)